LONDON — WikiLeaks founder Julian Assange was refused bail and jailed for a week by a British court Tuesday, pending an extradition hearing over alleged sex offenses in Sweden.

Assange turned himself in to U.K. police earlier in the day in the latest blow to his WikiLeaks organization, which faces legal, financial and technological challenges after releasing hundreds of secret U.S. diplomatic cables.

Swedish prosecutors had issued an arrest warrant for the 39-year-old Australian, who is accused of sexual misconduct with two women.

Assange surrendered at 9:30 a.m. local time (4:30 a.m. ET) Tuesday. The U.K.'s Guardian newspaper reported that Assange later arrived at a London court accompanied by British lawyers Mark Stephens and Jennifer Robinson.

During his court appearance, Assange said he would fight extradition to Sweden and he provided the court with an Australian address. Britain's Sky News reported that Assange was receiving consular assistance from officials at the Australian High Commission.

The next court hearing is scheduled for next Tuesday, and Assange will remain in custody until then because he was deemed to be a flight risk.

Judge Howard Riddle asked Assange whether he understood that he could agree to be extradited to Sweden. Assange, dressed in a navy blue suit, cleared his throat and said: "I understand that and I do not consent."

The judge said he had grounds to believe that the former computer hacker — a self-described homeless refugee — might not show up to his next hearing if he were granted bail.

Arguments during the hour-long hearing detailed the sex accusations against Assange, all of which he has denied.

Australian journalist John Pilger, British film director Ken Loach and Jemima Khan, former wife of Pakistani cricketer and politician Imran Khan, all offered to put up sureties to persuade the court Assange would not flee.

Pilger, who offered 20,000 pounds ($31,600), told the court: "These charges against him in Sweden are absurd and were judged absurd by a senior Swedish prosecutor.

"It would be a travesty for Mr. Assange to go within that kind of Swedish system."

Attorney Gemma Lindfield, acting on behalf of the Swedish authorities, outlined one allegation of rape, two allegations of molestation and one of unlawful coercion stemming from Assange's separate sexual encounters in August with two women in Sweden.

Lindfield said one woman accused Assange of pinning her down and refusing to use a condom on the night of Aug. 14 in Stockholm. That woman also accused of Assange of molesting her in a way "designed to violate her sexual integrity" several days later.

A second woman accused Assange of having sex with her without a condom while she was asleep at her Stockholm home.

Assange's lawyers have claimed the accusations stem from a "dispute over consensual but unprotected sex" and say the women only made the claims after finding out about each other's relationships with Assange. WikiLeaks lawyer Stephens says the case has taken on political overtones — a claim Swedish officials have rejected.

In response to the decision to refuse bail, WikiLeaks tweeted: "Let down by the UK justice system's bizarre decision to refuse bail to Julian Assange. But #cablegate releases continue as planned."

After the hearing, Assange was taken to Wandsworth Prison in London, NBC News reported. Wandsworth is the largest prison in the U.K., currently able to hold 1,665 prisoners.

In Sweden, prosecutor Marianne Ny told a news conference that the sexual misconduct case was not connected with his work releasing secret U.S. diplomatic cables, according to newspaper Aftonbladet. "We have nothing which indicates that this is a plot," she said.

Assange had been staying at an undisclosed location in Britain since WikiLeaks began publishing hundreds of U.S. diplomatic cables online last month.

Assange denies the sexual misconduct allegations, which his lawyer Stephens says stem from a "dispute over consensual but unprotected sex."

'He is not violent'
One of the women involved in the sexual abuse allegations told Aftonbladet that she had voluntary relations with him and had never wanted him to be charged with rape, the Guardian said.

"He is not violent and I do not feel threatened by him," she said — anonymously — according to the paper.

Despite Assange's legal troubles, a WikiLeaks spokesman insisted the flow of secret U.S. diplomatic cables would not be affected. He also downplayed efforts to constrict the group's finances after both Visa and MasterCard cut off key funding methods Tuesday.

"This will not change our operation," spokesman Kristinn Hrafnsson told The Associated Press. As if to underline the point, WikiLeaks released a dozen new diplomatic cables, its first publication in more than 24 hours, including the details of a NATO defense plan for Poland, Estonia, Latvia and Lithuania that prompted an indignant response from the Russian envoy to the alliance.

'Poison pill'
Meanwhile, the Guardian reported that WikiLeaks had no current plans to issue the code for an encrypted version of the rest of its documents — which has been called a "poison pill" — that would enable them to be published instantly, as it had threatened to do if its staff were arrested.

The organization's room to maneuver has been battered by Web attacks, cut off by Internet service providers and is the subject of a criminal investigation in the United States, where officials say the release jeopardized national security and diplomatic efforts around the world.

But amid Assange's personal legal troubles, his website continued to reveal state secrets.

In the latest release, the Guardian reported that, according to diplomatric cables, NATO has drawn up secret plans to defend the Baltic states, Estonia, Latvia and Lithuania, and Poland against any Russian threat.

Nine NATO divisions were identified for combat operations in the event of Russian aggression and countries were grouped together in a new regional defense scheme codenamed Eagle Guardian, the cables said.

'Dangerous'
Pentagon spokesman Col. David Lapan called the WikiLeaks' disclosure "dangerous" and said it gives valuable information to the nation's enemies.

NBC News reported that jihadists with connections to al-Qaida have started communicating online about the release.

"We want to exploit this document," one reportedly wrote.

U.S. Attorney General Eric Holder said Monday the Obama administration was considering using laws in addition to the U.S. Espionage Act to possibly prosecute the release of government information by WikiLeaks.

WikiLeaks also came under increasing financial pressure Tuesday. Collecting individual donations — the mainstay of its operations — became more difficult after credit card companies said they would refuse to process donations to the site.

Visa Inc. said it would "suspend Visa payment acceptance on WikiLeaks' website pending further investigation into the nature of its business and whether it contravenes Visa operating rules." MasterCard said it would suspend payments "until the situation is resolved."

PayPal Inc., a popular online payment service, has already cut its links to the website, while Swiss authorities closed Assange's new Swiss bank account on Monday, freezing tens of thousands of euros, according to his lawyers.

WikiLeaks is still soliciting donations through bank transfers to affiliates in Iceland and Germany, as well as by mail to an address at University of Melbourne in Australia.

NBC News, msnbc.com staff, The Associated Press and Reuters contributed to this report.

Video: Assange's lawyer: This will 'go viral'

Closed captioning of: Assange's lawyer: This will 'go viral'

>>>the news out of london that
julian
assange has been denied bail as he awaits extradition to sweden, which he says he will fight. we have some pictures for you. this is the secured vehicle.
julian
assange is in there. he was being taken from the courthouse to jail. his next court appearance
december 14th
. his main lawyer came out on to the courthouse steps to react to what had just happened. let's play that for you.

>>we've seen today mr. assange in custody. that was unfortunate. but wikileaks will continue. wikileaks is many thousands of journalists reporting news around the world. a renewed application will be made. the position, as we speak at the moment, is that we are in the rather the exotic position of not having seen any of the evidence that mr. assange is accused of. under those circumstances, it's very difficult to mount bail application on those grounds. as i'm sure you would all appreciate. we have heard the jobs today to say he wishes to see the evidence himself. i think he was impressed by the fact that a number of people who have prepared to stand up on behalf of mr. assange and prepare his innocence. we will see another bailout application and those are the tipoff.

>>that is just part of what yulegen assange's lawyer has to say. this will be really fascinating to watch.
julian
assange, as you may recall, if he or his organization faced charges or if he was arrested, he would unleash other cables. obviously, that's been a problem for the obama administration and according to the obama administration many members of congress, a serious threat to
national security
. other members of weeky leikileaks and supporters say there will be more coming out tonight. we will continue to follow this story developing out of london.

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